Cyclic process of recovering metallic tin.



cn'rrnn orlrrj c PATENT OFFICE.

Fl'tirNZ- VON hi'll'G'lCLGEN, OF HOUTOKHSS ROCK; VIRGINlA, AND GlfiOltGlCO. SEWAR'D. OF NEW I YORK, N. Y.

CYCLES PBOCESQ O'F RECOVERING METALLIC TIN.

Specification of Letters Patent.

Patented March 24, 1908.

Application filed June 10. 1907. Serial No. 378,294.

To all whom it may, concern:

' lie it known that we, FRANZ yon Kifonir ,JRQEN, a subject of thc lilnipcror of Gcrinany, Q residing at l'lolcombs Rock, Virginia, and "Girlonon U. HIE-WARD, a citizcn ol the lnilcd Stilton, residingot Nov York city, New York, l'iaii'c iirvcnlci'l certain now and usel'ul lni iirovemcuts in Cyclic Procccscs ol' Recovering Metallic lin, of which tho tulhH-"i'lllgi' is a spew-ilicntiou This: invcnlion rclotcs to thc rr-eovnry ol' lin as; a. znctal from materials with which it is associated in the metallic stato Several electrolytic pri'ui'csscs have been proposcd by which tin is stripped from tin-coated iron scrap (("u'nnionly known as tin scrap with the l'ornurtion of hydrous tin chlorids,

from which tho tin is precipitated by elcc- (irolysisi in some prom-sues lhc detinning and the subsequent precipil:ition ol' tho metallic tin arc done in tho sonic iwg-ssicl, using the scrap tin as tho onodc. in other proccssos lhc tin scrap is first 'ireatcd to remove tho coating ol lin mu] ihc solutions thus l'ornicd are electro l ned in a, sccond stop, preripitulini, l he in in ihc rnoi'allic al'atc. Finch clm'trolylic proc- (rsms arc not coniinuous. as tho solution conluhcinn; tho lin inusi ho rcnio'vod as soon as tho liu is et-;h:uisic l lhcrcl'loin and hither thrown away or used to treat now quanlii'. s ol {in scrap. zuh exlnuzstion of the tin is :icroniplishcd qui kly and tho rciilonishing ol' 1hrchwtrolrlic :anlis must bc rcpeatcd l'rcquontlyg Hlzllilllgi: h prorvss an intermitioiut' one. Such prorcsses have also tho disidroutage that hc in \\hi('h is separaifml when the solution approm-hes exhaustion. is in a r l spongy slalo lucvitnhly sonic iron is )llll,;lll llllo so .idion with ihe tin and this .zucllinulalwa, ii the liquor is'uscd ovci" Him m "1 'll" a um Hit (or J1:] i): (pm ii y. us :H'iULillHllHlHH! happens also when the tin scrap is uscd ll c unodo and (logs tho elcchas licen lll. use sonic tnno.

trolytc al'lcr it .Aflfl'flillilg lo tho prcsont cyclic process, tho SOlUllOH and rodeposition ol tho tin arc cllcclcd in two stages: in tho li'r'st stage, tho tin removed from tho scrap by an anhylrous rc cent which a selective, solvcnt of spcc lically by dry chlorin, gascous or in an drous' solutii'in. in tlic 'occond stago, lic msulting tin compound, is'pocifically anhydrous ,stannic chlorid, is converted intoan electrolyte, as by diasolving it in'watcr, and

is dcconi )osed with insoluble anodes the l i V 7 anode product being; dricd and uscd to trout a second chargc of scrap and tho pure cohcreut tin being: deposited at tho ('athodc.

In carrying out the proccssby tho usc of chlorin the tin scrap or other tin hearing: inatcrial may bc subjected to the action of cilhcr dry chlorin gas or a solution oi chlorin in an. anhydrous liquid, such as stannic chlorid or carbon ictrachlorid, thc tcmpcraturc of tho chargc bcing maintained within scimblc limits. Tho tin is thcrcby converted into stannic chlorid, which is rcnio'vcd from tho rosidual iron and is clcctrolytically de composed. The electrolysis is preferably cll'cctcd by dissolving thc stannic chlorid in water and producing two solutions ol different concentration, one of specific gray ity 1.3, the other of specific gravity 1.15. The solution of higher dcnsity is placed in thc closed anode COIIlI'HLItIDODl) of a diaphragm cell and that of lower dcnsity is placcd in the sail llOl lo conu'iartmont. The insoluble anodes may bc of graphite and the cathodes shoots cl puro tin. The ccll may contain a scries ol altcrnatc anode and cathodo coinpartmonts. Under those conditions and by the uso of a currcnt of suitable cathodc dcnsity, ihc iin is dcpositod either as a compact coating or as :unooth llcxiblo crystals which can be easily consolidated by niodcrzitc pressuro into dcnsc coherent masses, suitable for melting. The crystalline dcposit should be 1 moved occasionally to III'OVOllt its bridgingacross to the diaphragm. Tho chlorin is led from tho anodc conniartnicnt, dricd, for

example by calcium chlorid and sulfuric I and stannic chlorid from othcrvcsscls being shnultancously suppliml to thc coll.

'lhc process is cspccially applicable not only to 'lli'rhsrn'op but to tho product containing; linclydi'vidcd tin obtaincd by l'()(.ll.l(7lllg a inixturcol tin orc and carbon at a modcratc lLOIYlDGILhllIG.

o claim: L

'1. Tho cyclic proccss 0f rccovoring metallic tin from t rrbcaring materials; which consists in treating a charge of the material min with an anhydrous selective solvent of tin and producing a tin compound, deconiposi ing said compound into metallic tin and an acid radical, and employing said acid radical to treat another charge of material.

2. Thecyclic process-of IGCOVP-Illlg metalstannic chlorid, hydrating-said chlorid, de-' composing the hydrated chlorid into metallic tin and chlorin, drying said chlorin and employing it to treat another charge of material.

4. The cyclic process of recovering metallic tin from tin-bearing materials, which consists in treating a charge of the material with an anhydrous selective solvent of tin and producing a tin compound, electrolytically decomposing said compound, and em ploying the anode product to treatanother charge of material.

5. The cyclic process of recovering metallic tin from tin-bearing materials, which consists in treating a charge of the material with an anhydrous selective solvent of tin and producing a tin compound, electrolytically decomposing said compound, and employing the anode product in a dry state to treat another charge ol material.

6. The cyclic process of recovering metallic tin from tin-hearing materials, which consists in treating a charge of the material With anhydrous chlorin and producing stannic chlm'id, clcctrolytically decomposingsaid chlorid, and employing the elect rolvtic chlorin iri a dry state to treat another charge of material.

7. The cyclic process of recovering metallic tin l'rom tin-bearing materials, which consists in treating a charge of the material with an anhydrous selective solvent of tin and producing a tin compound, dissolving said conmound in water, electr'olyzing the aqueous solution with an insoluble anode,

l'tll'lfiVlllg and dryingthe anion and employing it to treat another chargeof material.

s. The cyclic process of recoverin' metal-- lic tin from tin-hearing materials, which sists in treating a charge of the material with anhydrous chlorin and, producing stannic chlorid. dissolving said chlorid in water. e'lect-rolyzinp the aqueous solution with a insoluhle anode, removing and drying the electrolytic chlorin and employing it to treat another charge of material.

9. The cyclic process of recovering metallic tin from tin-hearin; materials, which consists in treating a charge ol the material with anhydrous chlorin and producing stannic chlorid, dissolving said chlorid in water to produce two solutions of different concentration, electroh'ziug said solutions by passing an electric current from an insoluble anode successively through. the more concentrated and less concentrated solution, removing and drying the electrolytic chlorin and employing it to treat another charge of material.

In testimony whereof, we aiiix our signatures in presence ol witnesses. a

FRANZ VON KUGELGEN. GEORGE O. SEWARD.

\Vitnesses as to the signatnreot' Franz von Kugelgen: 7

HARRY RILEY .linn, J. ll. Ween.

Witnesses as to the signature of George 0. Seward:

Jns'rix (7. Warren, (lno. h. Snu'aun. 

